Hi Jon:
Current first aid training is to leave the boot on to provide stability unless the foot is swelling so much that circulation might be impaired. For a bleeding wound direct pressure, boot and all, is the way to go.
Boots are cut away now by cutting the back off with a pair of safety scissors so that the boot is lifted off the foot as opposed to the foot being twisted as it comes out of the boot. Us first aiders don't do that, least not in Ottawa FD.
Of course this is all predicated on being near second (ambulance) and third (hospital) level medical care. As a Fire Fighter in rural Ottawa we can count on evacuation within 25 minutes so the boots stay on. If the Paramedic wants them off we will assist in cutting them away.
Put on my other hat, and as a soldier in the wilderness, I'd default to judgement call. If I do have to cut away a boot there's lots of time to undo it and pull out or cut off the laces. I'd still prefer to cut the boot away then to pull it off the foot.
Regardless, as per CF dress regulations; my drill boots are straight laced and my combat boots are cross laced, carefully ensuring that the outside lace is always over the inside lace.
Cheers! Mike